Beijing fined polluters more than 46.5 million yuan ($6.94 million) from January to June, the local environmental watchdog said Tuesday.

A total of 4,531 fines for pollution have been levied in the first half of the year when campaigns were held to combat especially air and water pollution.

Over 3,300 cases were found at mobile pollution sources which were fined more than 3.36 million yuan, while some 1,209 stationary pollution sources were fined a total of 43.2 million yuan, the municipal environmental protection authorities said at a press conference on Tuesday. 

Specifically, some 19.95 million yuan of fines came from air pollution cases, some 46.19 percent of the total amount, while water pollution cases made up some 18.74 percent of the total, the China News Service (CNS) reported.

Apart from penalties, operation suspension orders were given in 105 cases and people involved in two cases were put under administrative detention. In another two cases, related people were transferred to judicial authorities on suspicion of environmental pollution crimes, the environmental watchdog noted.

Currently, some 170 major polluters in Beijing are closely supervised every day, while random inspections check on other polluters. A total of 7,542 companies have faced such random pollution inspections, according to the CNS.

Beijing authorities have vowed to curb air pollution, cutting PM2.5 by 20 percent by 2017, and by 45 percent in 2022, the Xinhua News Agency reported in August 2015.